Add enable-app-shims to chrome://flags.

chrome/browser/resources/ntp4/apps_page.js

Index: chrome/browser/resources/ntp4/apps_page.js
diff --git a/chrome/browser/resources/ntp4/apps_page.js b/chrome/browser/resources/ntp4/apps_page.js
index 852887d79efd671f1b2e53c2e230620d9d6811b6..828d4d4cbc328ea0d855864dc4dc4849722caade 100644
--- a/chrome/browser/resources/ntp4/apps_page.js
+++ b/chrome/browser/resources/ntp4/apps_page.js
@@ -73,7 +73,7 @@ cr.define('ntp', function() {
       this.uninstall_.addEventListener('activate',
                                        this.onUninstall_.bind(this));
 
-      if (!(cr.isChromeOS || cr.isMac)) {
+      if (!cr.isChromeOS) {
         this.createShortcutSeparator_ =
             menu.appendChild(cr.ui.MenuItem.createSeparator());
         this.createShortcut_ = this.appendMenuItem_('appcreateshortcut');
@@ -140,12 +140,15 @@ cr.define('ntp', function() {
       this.details_.disabled = !app.appData.detailsUrl;
       this.uninstall_.disabled = !app.appData.mayDisable;
 
-      if (this.createShortcut_ && cr.isMac) {
+      if (cr.isMac) {
         // On Windows and Linux, these should always be visible. On ChromeOS,
         // they are never created. On Mac, shortcuts can only be created for
-        // new-style packaged apps, so hide the menu item.
+        // new-style packaged apps, so hide the menu item. Also check if
+        // loadTimeData explicitly disables this as the feature is not yet
+        // enabled by default on Mac.
         this.createShortcutSeparator_.hidden = this.createShortcut_.hidden =
-            !app.appData.packagedApp;
+            !app.appData.packagedApp ||
+            loadTimeData.getBoolean('disableCreateAppShortcut');
       }
     },